The present invention relates generally to the field of wireless telecommunication. More specifically, the present invention relates to the management of telecommunication services in wireless networks which support populations of subscriber units having dissimilar service configuration capabilities.
Those who provide wireless telecommunication services are typically licensed to use a specified portion of the electromagnetic spectrum within a specified geographical area. The more efficiently the provider uses the licensed spectrum, the more call traffic that can be conveyed, and the more revenues the provider can generate. Accordingly, service providers are motivated to use their licensed spectrum as efficiently as possible.
A progression of wireless communication standards has evolved. Generally, the spectrum is used more efficiently when telecommunication services are delivered in accordance with newer standards than when services are delivered in accordance with older standards. For example, older analog standards, such as the advanced mobile phone service (AMPS) set forth in TIA/EIA-553 use the spectrum less efficiently than more modern digital standards, one example of which is TIA/EIA-95-B, entitled: xe2x80x9cMobile Station-Base Station Compatibility Standard for Wideband Spread Spectrum Cellular Systemsxe2x80x9d, March 1999 (hereinafter TIA/EIA-95).
However, during a transition period which may continue indefinitely, newer standards coexist with older standards. To minimize waste of a service provider""s infrastructure and to maintain compatibility with an existing customer base, both newer and older standards are practiced simultaneously. This transition period and the coexistence of multiple standards generates numerous dilemmas.
For example, the TIA/EIA-95 CDMA standard has contemplated various features which were not implemented by some mobile switching center (MSC) manufacturers and by some subscriber unit manufacturers at first because few then-existing subscriber units or MSC""s could take advantage of the features. The negotiation of certain service configurations is one such imperfectly-implemented feature. While subscriber units and MSC""s might not have been perfectly compliant with published specifications, they nevertheless functioned acceptably well because the newer features were not needed.
Subscriber units then began to provide newer capabilities, all still in compliance with standards. One such newer capability is EVRC. However, in order to remain compatible with home and roamed-upon networks that could not operate with the newer capabilities, such subscriber units were programmed to default-out the newer capability. In particular, a large number of EVRC-capable subscriber units have been programmed to originate calls using the older 13 kb/s vocoding rate so that they could operate on systems that did not offer the EVRC service. Unfortunately, when thus programmed EVRC-capable subscriber units operate on EVRC-capable systems, they continue to originate calls using the older 13 kb/s vocoding standard even though both subscriber unit and MSC support the newer, more spectrally efficient standard. Since the vast majority of cellular calls originate at subscriber units, a significant waste of spectrum results.
One option for minimizing this unnecessary waste of spectrum would be to reprogram subscriber units to default to the newer capability, e.g., EVRC, in an existing customer base when the network supports the newer capability. However, this option is highly undesirable because it causes customer inconvenience and requires customer cooperation. Moreover, it can still prevent subscriber unit operation when the subscriber unit roams on networks which are not EVRC capable.
Another option for minimizing this unnecessary waste of spectrum is to follow the Service Negotiation or Service Order Negotiation processes set forth in the TIA/EIA-95 CDMA standard to negotiate subscriber units that originate calls into implementing EVRC. Negotiation processes generally occur when a first station, either a base or mobile, requests a service configuration of a second station, either a mobile or base. If the requested service configuration is acceptable, the second station may accept the requested service by returning an appropriate response message. If the requested service configuration is not acceptable to the second station, the second station may request an alternate service configuration of the first station. The first station may then accept the requested alternate service configuration or request yet another alternate service configuration, and so on.
While the negotiation processes work acceptably well in a population of homogeneous subscriber units having similar service configuration capabilities, these processes produce unwanted consequences in a heterogeneous population of subscriber units having dissimilar service configuration capabilities. The negotiation processes risk denying service or providing a less spectrally efficient protocol when used with subscriber units not capable of providing the desired service configuration, such as EVRC. In particular, if a base station were to request an alternate service configuration, such as EVRC, after a mobile station has requested a different service configuration, such as the default 13 kb/s service, conventional mobile stations would interpret the alternate request as a denial of the original request, e.g., a denial of 13 kb/s service. If the subscriber unit was not EVRC-capable, then the negotiation process would lead to the selection of analog service or to denial of service. Accordingly, a service provider may not simply attempt to negotiate a subscriber unit to EVRC service because the negotiation processes set forth in the standards would lead to a less efficient use of spectrum or a denial of service, which is an even worse consequence, if attempted on a subscriber unit not capable of providing the desired service configuration.
A database may be used to specify the service configuration capabilities of various subscriber units. Using such a database, a network may then negotiate subscriber units capable of implementing more than one service configuration to a more desired service configuration without unduly risking a denial of service or operation in accordance with an even less desired service configuration, such as analog service. Unfortunately, conventional techniques for forming such a database lead to undesirable and unreliable results. Cooperation from an assortment of different manufacturers of subscriber units may be required to obtain the data needed to populate the database. Such data are often unreliable and stale. Moreover, such data are often manually entered, which leads to further errors due to human factors. In addition, even if such data are obtained in an accurate form and entered in an accurate manner, the data soon become stale due to constant vendor revisions to subscriber units.
It is an advantage of the present invention that an improved method and wireless telecommunication network provide services for subscriber units with dissimilar service configuration capabilities.
Another advantage of the present invention is that a database is used to filter the application of a negotiation process which, when enabled by the database, negotiates subscriber units to alternate service configurations.
Another advantage of the present invention is that subscriber units that do exhibit only older service configuration capabilities are not negotiated away from their preferred service configurations.
Another advantage of the present invention is that subscriber units which are capable of newer service configurations may nevertheless default to less-preferred, older service configurations compatible with a wide range of networks, but be negotiated to the newer service configurations when the newer service configurations are supported.
These and other advantages are realized in one form by an improved method of operating a wireless telecommunication network to accommodate a population of subscriber units exhibiting dissimilar service configuration capabilities. The method calls for automatically storing, in a database, data specifying whether a subscriber unit is capable of providing a subject service configuration. A request to place an outgoing call from the subscriber unit is received. The database is evaluated to determine if said subscriber unit is capable of providing the subject service configuration. If this evaluation indicates that the subscriber unit is capable of providing the subject service configuration, the subscriber unit is requested to implement the subject service configuration.